.tool-box {
  margin-bottom: 20px;
  position: relative;
  &:after{
    content:"";
    clear:both;
    display: block;
  }
}

.pull-right{
  float:right;
}

.pull-left{
  float: left;
}

.pull-center{
  display: block;
  margin:auto;
}

.clear-fix{
  &:after{
    content:"";
    clear:both;
    display: block;
  }
}